The role of visual imagery in story reading: Evidence from aphantasia

Beyond words: Examining the role of mental imagery for the Stroop effect by contrasting aphantasics and controls

One of the best replicated and most famous effects in experimental psychology, the Stroop effect, describes interferences in cognitive processing when a color word is printed in a conflicting ink color. Recently, the controversial hypothesis was proposed that reading the color word triggers visual imagery, which then interferes with the perceived color, leading to the Stroop effect. Thus, the Stroop effect should not occur in aphantasics, i.e., in individuals with impaired mental imagery. We tested this intriguing hypothesis in a rare sample of 151 aphantasics and 110 controls. Results show that the Stroop effect was reduced in aphantasics, albeit still existing. For the first time, the present data show that an interference between mental imagery and perception is partially responsible for the Stroop effect.

"The Giant Black Elephant with white Tusks stood in a field of Green Grass": Cognitive and brain mechanisms underlying aphantasia

Aphantasia, a spectrum of inabilities creating and perceiving mental images, is becoming more of a focus in continued research to better understand functions of sensory perception and imagination. Current research on aphantasia is still in an era of exploration to find its underlying neural mechanisms, comorbidities and comparing levels of visual imagery to other cognitive functions. Through a systematic review, this article explores the most influential developments in aphantasia research. The search included 3 databases-PsycINFO, PubMed, and Web of Science. After a rigorous selection process, 52 studies are included in this review. The findings include new research themes across different studies such as relationships between aphantasia and diminished episodic and autobiographical memory, comorbidities including autism, attention, emotions, and neurobiological differences. By integrating diverse perspectives, this review aims to contribute to a deeper understanding of the cognitive processes underlying mental imagery and offers implications for further development in aphantasia research.

Aphantasia and autism: An investigation of mental imagery vividness

OBJECTIVE

The present study investigated whether autistic adults report different levels of mental imagery vividness than non-autistic adults, and, moreover, if autism is associated with aphantasia which is defined as a condition of reduced or absent voluntary imagery.

DESIGN AND METHODS

Clinically diagnosed and self-identifying autistic participants were compared with non-autistic participants in their mental imagery vividness (vision, sound, smell, taste, touch, bodily sensation and emotional feeling) and autistic traits using an online survey (N = 121).

RESULTS

The autistic group scored significantly lower than the non-autistic group on imagery vividness (d = -0.44), in addition to having a higher proportion of participants scoring at cut-off for aphantasia. Moreover, a similar difference was observed for the emotional feel (η2 = 0.11).

CONCLUSION

The vividness of visual and emotional mental imagery was on average lower for autistic individuals, with a higher proportion presenting at cut-off to be considered an aphantasic.

A Systematic Review of Aphantasia: Concept, Measurement, Neural Basis, and Theory Development

People with aphantasia exhibit the inability to voluntarily generate or form mental imagery in their minds. Since the term "aphantasia" was proposed to describe this, it has gained increasing attention from psychiatrists, neuroscientists, and clinicians. Previous studies have mainly focused on the definition, prevalence, and measurement of aphantasia, its impacts on individuals' cognitive and emotional processing, and theoretical frameworks synthesizing existing findings, which have contributed greatly to our understanding of aphantasia. However, there are still some debates regarding the conclusions derived from existing research and the theories that were constructed from various sources of evidence. Building upon existing endeavors, this systematic review emphasizes that future research is much needed to refine the definition and diagnosis of aphantasia, strengthen empirical investigations at behavioral and neural levels, and, more importantly, develop or update theories. These multiple lines of efforts could lead to a deeper understanding of aphantasia and further guide researchers in future research directions.

Cognitive strengths in neurodevelopmental disorders, conditions and differences: A critical review

Neurodevelopmental disorders are traditionally characterised by a range of associated cognitive impairments in, for example, sensory processing, facial recognition, visual imagery, attention, and coordination. In this critical review, we propose a major reframing, highlighting the variety of unique cognitive strengths that people with neurodevelopmental differences can exhibit. These include enhanced visual perception, strong spatial, auditory, and semantic memory, superior empathy and theory of mind, along with higher levels of divergent thinking. Whilst we acknowledge the heterogeneity of cognitive profiles in neurodevelopmental conditions, we present a more encouraging and affirmative perspective of these groups, contrasting with the predominant, deficit-based position prevalent throughout both cognitive and neuropsychological research. In addition, we provide a theoretical basis and rationale for these cognitive strengths, arguing for the critical role of hereditability, behavioural adaptation, neuronal-recycling, and we draw on psychopharmacological and social explanations. We present a table of potential strengths across conditions and invite researchers to systematically investigate these in their future work. This should help reduce the stigma around neurodiversity, instead promoting greater social inclusion and significant societal benefits.

Aphantasia and hyperphantasia: exploring imagery vividness extremes

The vividness of imagery varies between individuals. However, the existence of people in whom conscious, wakeful imagery is markedly reduced, or absent entirely, was neglected by psychology until the recent coinage of 'aphantasia' to describe this phenomenon. 'Hyperphantasia' denotes the converse - imagery whose vividness rivals perceptual experience. Around 1% and 3% of the population experience extreme aphantasia and hyperphantasia, respectively. Aphantasia runs in families, often affects imagery across several sense modalities, and is variably associated with reduced autobiographical memory, face recognition difficulty, and autism. Visual dreaming is often preserved. Subtypes of extreme imagery appear to be likely but are not yet well defined. Initial results suggest that alterations in connectivity between the frontoparietal and visual networks may provide the neural substrate for visual imagery extremes.